1. Field of the Invention
This invention relates to data transfer over wired, wireless, and/or optical transmission channels.
2. Background Information
As computing and communications applications become richer and more complex, it becomes desirable to support transfers of data between devices at higher and higher rates. The increasing popularity of consumer electronics, computing, and communicating devices, in various forms (e.g. mobile, hand-held, wearable, and fixed) and possibly with associated peripherals, indicates a clear demand for these types of devices and for connectivity (e.g. peer-to-peer and/or networked) between them. Unfortunately, present-day communications technologies fall short of providing the technical requirements necessary to support such demands.
Wireless connectivity may enable greater user experiences and possibly spur an increased demand for such devices. For example, wireless connectivity can provide enhanced capability; is expected to be easier to use; may encompass cost savings and increases in efficiency and productivity; and may increase possible device applications and/or deployments.
Use of such devices may include large data transfers and/or multimedia applications. For example, a cable replacement scenario for a computer, a consumer electronics device, or a similar device may need to support transfers of large amounts of data. Multimedia applications may handle multiple simultaneous streams of high-definition audio and/or video coming from devices such as business/entertainment systems and gateways.
Most existing wireless schemes transfer data via modulated continuous-wave carriers. In many cases, a portion of the radio-frequency spectrum is reserved for the exclusive use of the scheme. Such reservations allow these transfer schemes (e.g. commercial radio and TV broadcasts) to operate free of interference from other devices and without interfering with other systems.
Data transfers may be conducted over very narrow frequency bands in an attempt to occupy less of the frequency spectrum. However, such schemes may be more susceptible to increases in background noise level and to multipath interference. Some narrowband schemes may also be more likely to interfere with other systems (e.g. due to a higher concentration of energy in the particular frequency band being used).
Although battery technology is steadily improving, operating times between charges or replacement are still important factors in the design of portable devices. Complexity and cost of transmitter and receiver implementations are other important factors for consumer applications. Present-day solutions offer only a few of the necessary technical requirements. For example, some may provide low cost and low power consumption but only at low bit rate, while others may have higher bit rates but be unacceptable in terms of cost and/or rate of power consumption.
It is desirable to support high rates of data transfer. It may also be desirable for a scheme that supports high, medium, and/or low rates of data transfer to obtain one or more advantages such as 1) low power consumption, 2) low cost of implementation, and/or 3) an ability to coexist with interferers and/or with other frequency use. Other desirable advantages may include scalability with potential capability for backwards compatibility and/or an ability to determine position and/or location.